Car roof



July 19, 1932. NSALL 1,868,159

CAR ROOF Filed July 6, 1931 2 Sheets-Sheet l C. D. BONSALL CAR ROOF 2 Sheets-Sheet 2 Filed July 6. 1931 July 19, 1932.

Patented Jul 19, 1932 UNITEDFS'AITAFTES CHARLES DAVID BONSALL, or rrrrsisnnerr, fENNSYLVANiA, AssIGNon TO 1?." nimm- PHY COMPANY, or NEW KENSINGTON, PENNSYLVANIA, A 'oonronnrrIo or PENN I SYLVANIA.

can noor Applicationwfiled July 6,1931. s al No. 543,955.

This invention relates to'metal car roofs.

In the typical form of so-called neutral axis roof, the sheets aresecured together at their margins and arranged to form panels at one 5 level alternating withpanels at a different level, the adjacent panels being connected by vertically disposed web portions whereby the roof as awhole functions afterthemanner of a beam, with the upper and lower panels tak l0 ing care of their full share of the tensile and compressive stresses and with the connecting web portion taking care of the shearing stresses. The height of the web portion is limited both by manufacturing considerations and by the danger of failing under buckling and cross bending stresses. Where head room and tunnel clearance are limiting factors, this typical form has a great advantage due to the relatively small distance between the upper and lower surfaces thereof. The principal object of'the present invention is to increase the spread between the uppermost and lowermost portions of the roof and thereby impose on the upper and lower seam constructions a greater proportion of the tensile and compressive stresses and make it practicable to use lighter roof sheets and pro-.

duce a lighter roof construction.

In the accompanying drawings wherein like numerals refer to like parts wherever they occur, 7 V

Fig. 1 is a plan view of a portion of the car roof embodying my invention, I

Fig. 2 is a vertical longitudinal section through the roof on the line 22 in Fig. 1,

Fig. 3 is a vertical cross-section through one of the lowerroof seams;

Fig. 4 is a vertical cross-section through one-half of the roof on the line 4-4 in Fig. 40 1; and I Fig. 5 is a section similar to Fig.4 on the line 5-5 in Fig. 1.

The present roof comprises metal. roof sheets A that span from side plate B to side"- plate B of the car and are rigidly secured thereto and have upstanding flanges 1 along both side margins, said flanges being capped or straddled by inverted U-shaped seam covers 2 rigidly secured thereto by horizontal rivets 3.

narrow panels or steps 4 and the wide spread The body of each roofsheet Ais formed into a series of raised'panels Jorsteps 4 which flattenout into a s'inglep'lane near the ends 1 of the sheet where it rests upon the side plates B. Beginning on one side of the sheet, each successivestep or panel t is higherthan the one preceding it ,being connected thereto by a relatively narrow or low web 5.

While each individual web5 is relatively low or narrow, the webs are sufficiently numerous to QQ raise one margin ofthe sheet considerably higher'than the other margin and considerably higher than would be feasible with a sin gleofl'set of'the sheet. As stated above, the side margins of the 5. roof sheets-Aare provided with upstanding flanges 1; The. side flanges l of adjacent roof sheets abut against each other and are straddled by asea'm cover Q'rigidly secured by rivets ;3 extending horizontally through said seam cover and said flanges, At the eaves, the ends of-the seamcover are turned down and riveted t'o'the side plates. Preferably the roof sheets are all formed alike, with the high marginal flanges of adjacent sheets-" abutting against each other and with the low marginal flanges. of adjacent sheets abutting against each other."

:"On account ofthemultiplicity of relatively betweenthe upper and lower seams, there is aconsiderable concentration of the tensile and compressive stresses at and near the lower and upper seams, respectively, the in 'termediate portions of'the'roof sheets 'heing' subject to -relatively little tensile and cornpressive stresses." Accordingly, "it is desirable to make the seam caps 2"of relatively large cross-sectional area; In so far as taking care or' stress isconcerned,the'principal duty? of the roof sheets is to resist the shearing, I

buckling and cross-bending stresses arising from beam action, that; is, to provide'the factors that-makefthe upper andlower seam constructions function as the compression and tension members of a single beamf In performing this function, the shallowness of y theindividual webs5 and the narrowness of v the individual steps 4 are items of importance, as such webs and panels afiord mutualfa A support and adaptthe body of thesheet to panels of adJacent sheets being joined to AA brace the seam constructions and hold such 'gether at a'lower level.

A V seam constructions to their work as members Signed at New Kensington, Pennsylvania,

' of the singlebeam. In consequence of the this 29th day of June, 1931.

natechitbeeomes feasible to-use thinner gage A sheets :than' would otherwise be practicable for a given strength of roof, and'the total 7 weight o f the IfQQf may beconsiderably re- A 'duced. o

1o Whilethe seam construction hereinbefore mentioned is simple, strong and well adapted for use with the roof sheets described, other seam constructions may .be eused in placerof i. V ,7

r it and the marginal portion of'the roof s eet A A A i A a i S9 modifiedconformably:theretmif necessany. Y

1.,ACSJ:IOOfCOIIIPIElSlIIgJYOOf ShEBtS whose I longitudinal side portions-arearespectively V Y 1 .7

o aboveand-belowthe levelofithe longitudinal 2, e v middle portion,-said side portions:beingipro- A vided with upstanding flanges, and lthe flanges at the lower sides of adjacent-sheets being secured-;--.together flatwi-se, and ithe t 1 flanges at't-he higher sides ofadjacentsheets A so being-secured togetlierfiatwise. Y.

,2. Ajcarroofcomprising roofshe'etswhose body portions compriselongitudinal side panels and at least one intermediate panel,

all at differentlevels', ithe-lower sides of ad- AA A I v AA .1525

j acent sheets being secured together .flatwise, andithe' higher sides of acen't sheets being secured together Fflatwise.

- 3. A carroofcomprisingroofsheets whose body-portions comprise longitudinal side Y AA panels and at least-one intermediate panel, all at different levels, said :side panels being r-provided with upstanding :flanges, and the flanges at the lower sides" of :adj accent sheets being secured together flatwise, and :the i a g o L nall-y thereof and mer ing-near their-ends *r JOined itogether 'at'onelevel andtheglower flanges .at the higher sides ofadjacent sheets being secured together flatwise. Y

4:. A car roof sheet comprising :a series 10f tmore than two panels extending longitudiam into a common plane, eachsuccessive panel ,being higherithan the one-that precedes it.

" 5. A car roof sheet-comprisinga:series of more than two panels extending longitudibd nally thereofand merginggnear'their ends A I V into a common plane, said sheet-having side marginal flanges and downturned ends, each A snccessive panel being higher than the one that precedes it; A

16, Acarroof-comprising roof sheets with A J "5123A upstanding flanges along; their sides and seam caps straddling the flanges of adjacent sheets-and secured :thereto, each sheet. ;comprising an uppers'ide panel anda lower side --'.pan el and a pluralityofintermediate panels A 1 A J A 1 A 7 extending substantiallyvthe width-of the car,

each successive panel ofa sheet. being'high-er than thenext preceding panel ofsaid sheet, the upper-panels of adjacent sheets'bei-ng manner in whichthe elements are coordi- CHARLES DAVID B ONSALL. A 

